Pressure fluid motor



1 9, 1936. EJG. GARTIN 2,040,842

PRES SURE FLUID MOTOR Filed Aug. 29, '1952 Eig.1. 26

a 4,. Am. 021%.

Patented May 19, 1936 PRESSURE FLUID MOTOR Elmer G. Gartin, Claremont, N. H., assignor to Sullivan Machinery Company, a corporation of Massachusetts Application August 29, 1932, Serial No. 630,862

8 Claims.

This invention relates to pressure fluid motors and more particularly to improvements in the fluid distribution means of such motors.

An object of this invention is to provide an improved pressure fluid motor. Another object is to provide an improved fluid distribution means for a pressure fluid motor. A further object is to provide an improved fluid distributing valve mechanism for a pressure fluid motor. These and other objects will, however, subsequently more fully appear.

In the accompanying drawing there are shown for purposes of illustration one form and three modifications thereof which the invention may assume in practice.

In this drawing,

Fig. 1 is a central, longitudinally extending-sectional view through the preferred illustrative embodiment of the improved pressure fluid motor.

Fig. 2 is a View similar to Fig. 1 showing the valve and motor piston in a different position.

Fig. 3 is a transverse vertical sectional view taken substantially on line 33 of Fig. 2.

Fig. 4 is a fragmentary sectional view showing a modified form of valve mechanism.

Fig. 5 is a detail sectional view showing a further modified form of valve mechanism.

Fig. 6 is a detail sectional View showing a still further modified form of valve mechanism.

In the illustrative construction shown in Figs. 1 to 3 inclusive there is shown a motor cylinder I having a bore 2 containing a reciprocable hammer piston 3. The hammer piston is provided with a usual striking bar 4 adapted to actuate percussively the shank 5 of a drill steel supported within a chuck 6 carried within the forward end of the motor cylinder. The motor cylinder is provided with a reduced bore 1 adapted to receive and guide the striking bar 4 in the manner shown in Fig. 2. Seated against a radial flange 8 integral with the motor cylinder is a rear motor head and valve chest element 9, the head being secured to the motor cylinder in any suitable manner. Arranged within the rearward end of the motor cylinder and head is the improved valve mechanism generally designated [0.

Now referring to the improved fluid distribution means for effecting reciprocation of the motor piston, it will be noted that arranged within a bore l 5 formed in the head 9 is a usual throttle valve 82 which controls the flow of pressure fluid from a suitable source of supply through a passage E3 to a valve chamber I4. Arranged within the valve chamber is a flat annular valve [5 having a forwardly projecting sleeve-like guiding portion I6 fitting within the rear end of the cylinder bore and provided with a central opening [7. The head block 9 at the rear side of the valve chamber is annularly grooved at l'8,

while the rear face of the motor cylinder is arouately or annularly grooved at l9. Formed about the opposite sides of these grooves are annular seats 20 and 2| respectively with which the opposite faces of the valve l5 engage upon movement of the valve into its different operating positions. The rear area of the valve is cut away or relieved at 22 in such manner as to equalize the pressure area on the forward face of the guide sleeve it. The valve chamber is annularly grooved at 23 and the supply passage l3 communicates with this groove. This groove also communicates with the annular groove l8 through a slot 24 and with the annular groove l8 through a similar slot 25. Communicating with the valve chamber at the forward side thereof is a longitudinal passage 26 which communicates through a radial port 21 with the forward end of the cylinder bore. An annular seating surface 28 surrounds the port opening of the passage 25 so that when the valve is in its forward position, as shown in Fig. l, communication between the valve chamber and the passage 26 is entirely out off. A series of radial piston controlled passages 29 communicates with the cylinder bore intermediate the ends thereof for connecting the cylinder bore directly to exhaust.

In the operation of the improved pressure fluid motor above described, when the throttle valve I2 is in the position shown, pressure fluid may flow through the passage l3, and when the distributing valve I 5 is in the position shown in Fig. 1, the valve is seated against the annular seats respectively surrounding and to the inside of the groove 1 9, cutting off communication between the groove 23 and the front end'of the cylinder bore, and pressure fluid then flows from the annular groove 23 through the valve chamber past the rearward surface of the valve and through the opening ll in the valve to the rear end of the cylinder bore, the pressure fluid acting on the rear pressure area of the motor piston to drive the latter forwardly to effect its working stroke. At this time the forward end of the motor cylinder is connected to exhaust through passages 29. When the piston, as it moves forwardly, overruns the exhaust passages 29, the pressure within the rear end of the cylinder bore is vented to atmosphere, and as a result of this appreciabledrop in pressure and the line pressure in the groove l9 acting on the forward pressure area of the valve,

inder bore, and pressure fluid then flows through the passage I3, annular groove 23 and through the valve chamber at the forward side of the valve, and thence through the longitudinal passage 26 and port 21 to the forward end of the cylinder bore, the pressure acting on the forward pressure area of the piston to effect retraction thereof. At this time the rear end of the cylinder bore is connected to exhaust through the passages 29. As the forward edge of the hammer piston overruns the exhaust passages 29, the pressure at the forward end of the cylinder bore is exhausted to atmosphere, thereby causing a sudden drop in the pressure within the passage 26 and the valve chamber 'at the forward side of the "valve, and as a result, the pressure in thegroove l8 acting on the rearward pressure area of the valve effects throwing of the latter from the position shown in Fig. 2 to the initial position shown in Fig. 4, these operations being repeated during normaloperation of the motor.

- In the form'of the invention shown in Fig. 4,

the fluid distributing valve 30 is provided with a sleeve-likeflange 3! fitting the bore 32 of the 'valve chamber and a similar sleeve-like flange 33 fitting the boreof the motor cylinder. In this form' ofthe invention theannular groove I8 formed in the head block is omitted, and the valve is annularly grooved at 34 on its rear face. A port 35 formed in the flange 3| connects the groove 23 with the groove 34 and the rearward edge of the flange 3| is notched at 36. The groove 23 is also '4, pressure fluid flows through the passage I3Vand groove 23, through the slot 36, through the valve chamber at the rear side of the valve, and centrally through the valve to the rear end of the motor cylinder to efiect, the forward working stroke of the motor piston. As in the form of the invention above described, when the exhaust ports 29 are uncovered by the piston, the pressure within the rear end of the motor cylinder is appreciably reduced, thereby causing the valve to be thrown from the position shown in Fig. 4 to its rearward position by the pressure flowing from groove 23, through slot 31, to groove 38. When the valve is in its rearward position, pressure fluid flows through the port 36 to the groove 34, and when the pressure at the forward side of the valve is reduced by the enhausting of pressure within the forward end of the motor cylinder, the pressure in the groove 34 effects throwing of the valve from its rearward position to its initial position shown in Fig; 4. Otherwise, the operation of this form of the invention is identical to that described above.

In the modified form of construction shown in Fig. 5, the valve mechanism is identical to that described in the preferred form of the invention with the exception that the valve chamber 40 is provided with annular seats 4| and 42 for receiving the valve flange as the valve reciprocates during normal operation of the motor. ''The operation of this form of the invention isidentical to that above described. it

In the modified form of construction shown in Fig. 6, the sleeve-like portion of the valve fitting within the bore of the motor cylinder is made separate from the valve and is held rigidly in position between the head block 9 and the motor cylinder. This sleeve-like guide member is bore.

numbered 43 and provides a cylindrical surface 44 on which a flat annular disc type valve 45 is guided. The member 43 is provided with openings 46 through which pressure fluid flows from the valve chamber [4 to the central opening 41 formed in the member 43 and which communicates directly with the rear end of the cylinder The operation of this form of the invention is similar to that above described with the exception that when the valve is in the position shown in Fig. 6 pressure fluid flows from the groove 23 through the valve chamber at the rear side of the valve and through the openings 46 and 41 to the rear end of the cylinder bore. Otherwise the operation of this form of the invention'is identical to that above described.

It is to be noted that the term annular is used in this application to include not only completely circular formation, but also substantially completely circular formations.

While there are in this application specifically described one form and three modifications thereof, which the invention may assume in practice, it will be understood that this form and these modificationsare shown for purposes of illustration,

parting from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In apressure fluid motor, a cylinder having a bore, a piston reciprocable therein, a head block closing the rear end of the cylinder bore, and fluid distribution 'me-ans for effecting reciprocation of said piston including a valve chamber formed by said head block and the cylinder, an automatic fluid distributing valve'reciprocably mounted in said valve chamber for controlling the supply of fluid to the opposite ends of said cylinder, said valve arranged with respect to the cylinder bore at a point not traversed by the piston, and when in its forward position seating directly on the rear end of the cylinder, said valve chamber having annular pressure receiving grooves surrounded by annular seats with which said valve engages upon reciprocation thereof,

one groove being formed in said head block and the other groove being formed in the rear end of said cylinder. I

2. In a pressure fluid motor, a cylinder having a bore, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest arranged at the rear end of the cylinder and having a valve chamber formed therein, an annular groove surrounding the valve chamber, annular grooves surrounded by annular seats formed on the opposite sides of the valve chest, an annular disc valve chest grooves, and means for supplying pressure fluid to said first mentioned annular groove. 7

3. In a pressure fluid motor, a cylinder having -a bore, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest arranged at the rear end of the cylinder and having a valve chamber formed therein, an annular groove surrounding the valve chamber, annular grooves surrounded by annular seats formed on the opposite sides of the valve'chest, an annular disc fluid distributing valve reciprocably mounted in said valve chamber for controlling the supply of pressure fluid to the opposite ends of the cylinder and arranged with respect to the cylinder bore at a point not traversed by the piston, Said valve when in its opposite positions seating on difierent ones of said annular seats and alternatively admitting pressure from said first mentioned annular groove to opposite ends of said cylinder past the outer edge of said disc valve, passage means connecting said first mentioned annular groove with said annular valve chest grooves, and means for supplying pressure fluid to said first mentioned annular groove, said valve being thrown in one direction by line pressure in one of said annular grooves acting on one pressure area of the valve when a lesser piston controlled pressure exists in the other annular valve chest groove and acts on the opposed area of the valve.

4. In a pressure fluid motor, a cylinder having a bore, a piston reciprocable therein, a. head block closing the rear end of the cylinder bore, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed by said head block and the cylinder, an automatic fluid distributing valve reciprocably mounted in said valve chamber for controlling the supply of fluid to the opposite ends of the cylinder, said valve arranged with respect to the cylinder bore at a point not traversed by the piston, and when in its forward position seating directly on the rear end of the cylinder, said valve having a sleeve-like guide portion fitting the cylinder bore and said valve chamber having annular pressure receiving grooves surrounded by annular seats with which said valve engages upon reciprocation thereof, one groove being formed in said head block and the other groove being formed in the rear end of said cylinder, and said valve further formed to provide an area facing rearwardly and constantly subject to like pressures to those acting on the forward end of said sleeve-like guide portion.

5. In a pressure fluid motor, a cylinder having a bore, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest arranged at the rear end of the cylinder and having a valve chamber formed therein, an annular groove surrounding the valve chamber, annular grooves surrounded by annular seats formed on the opposite sides of the valve chest, an annular disc fluid distributing valve reciprocably mounted in said valve chamber for controlling the supply of pressure fluid to the opposite ends of the cylinder and arranged with respect to the cylinder bore at a point not traversed by the piston, said valve having a sleeve-like guide portion fitting the cylinder bore and said valve in its opposite positions seating on said annular seats, and said valve having a surface facing oppositely to the effective forward surface of said sleeve-like guide portion constantly subject to cylinder pressure in the rear end of the cylinder, passage means connecting said first mentioned annular groove with said annular valve chest grooves,

and means for supplying pressure fluid to said first mentioned annular groove.

6. In a pressure fluid motor, a cylinder having a bore, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest arranged at the rear end of the cylinder and having a valve chamber formed therein, an annular groove surrounding the valve chamber, annular grooves surrounded by annular seats formed on the opposite sides of the valve chest, an annular disc fluid distributing valve reciprocably mounted in said valve chamber for controlling the supply of pressure fluid to the opposite ends of the cylinder and arranged with respect to the cylinder bore at a point not traversed by the piston, said valve having its outermost periphery continuously subject to the pressure in said first mentioned annular groove and having a sleeve-like guide portion fitting the cylinder bore, and said valve when in its opposite positions seating on said annular seats passage means connecting said first mentioned annular groove with said annular valve chest grooves, and means for supplying pressure fluid to said first mentioned annular groove, said valve being thrown in one direction by line pressure in one of said annular grooves acting on one pressure area of the valve when a lesser piston controlled pressure in the other annular valve chest groove acts on the opposed area of the valve.

7. In a pressure fluid motor, a cylinder having a bore, a piston reciprocable therein, a head block closing the rear end of the cylinder bore, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed by said head block and the cylinder, an automatic fluid distributing valve reciprocably mounted in said valve chamber for controlling the supply of fluid to the opposite ends of said cylinder and having oppositely facing portions constantly exposed to the pressure conditions in one end of the cylinder, and when in its forward position seating directly on the rear end of the cylinder, said valve chamber having annular pressure receiving grooves surrounded by annular seats with which said valve engages upon reciprocation thereof, one groove being formed in said head block and the other groove being formed in the rear end of said cylinder.

8. In a pressure fluid motor, a cylinder having a bore, a piston reciprocable therein, a head block closing the rear end of the cylinder bore, and

fluid distribution means for effecting reciprocation of said piston including a valve chamber formed by said head block and the cylinder, an automatic fluid distributing valve reciprocably mounted in said valve chamber for controlling the supply of fluid to the opposite ends of said cylinder and having oppositely facing portions constantly exposed to the pressure conditions in the rear end of the cylinder, said valve arranged with respect to the cylinder bore at a point not traversed by the piston, and when in its forward position seating directly on the rear end of the cylinder, said valve chamber having annular pressure receiving grooves surrounded by annular seats with which said valve engages upon reciprocation thereof, one groove being formed in said head block and the other groove being formed in the rear end of said cylinder,

ELMER G. GARTIN. 

